Oxygen Sensor Description
Oxygen sensors, or O2 sensors, are required to perform a critical function on your vehicle in the harshest of environments: Measuring the oxygen content of the exhaust just after it leaves the cylinders. The oxygen sensor has to accurately check this red-hot exhaust hundreds of times per minute and send that data to the vehicle computer. The fuel/air mixture hangs in the balance, and you're probably familiar with the symptoms of a bad oxygen sensor: Black smoke from the exhaust, a rotten-egg odor, and poor performance and fuel mileage.
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